WESTMINSTER can often be a confrontational and cacophonous place but when it speaks with one clear defiant voice, it is a powerful force to behold.

As Theresa May, dressed in sombre black, rose to address a packed chamber about Wednesday’s terrorist attack, the dropping of a pin could be heard.

She began her statement with a clear act of defiance to those who would try to silence Britain’s democracy: “We meet as normal - as generations have done before us and as future generations will continue to do - to deliver a simple message: we are not afraid and our resolve will never waiver in the face of terrorism.”

She ran through the details of Wednesday’s terrible events but one, unknown before, stood out; that among the injured were people of 10 different nationalities, underlining what a global city London is.

As Mrs May progressed through her statement, the emotional high point came when she spoke of Keith Palmer, the police officer, so cruelly stabbed to death by the knife-wielding terrorist as he was simply doing his job to protect those who work in Parliament.

She briefly ran through his background as a husband and a father, who had devoted his life to the service of his country, first as solider and then as a member of parliamentary protection team.

But lumps appeared in throats and tears welled up in eyes as the PM declared that Keith died doing the job he loved. “He was every inch a hero and his actions will never be forgotten.”

Later on, her Tory colleague Nigel Evans, the former Deputy Speaker, suggested to nodding heads that at some point in the future it might be appropriate to place a memorial for Keith, recognising his selfless act of heroism.

Another key moment came when Mrs May gave, albeit scant, details of the terrorist: British-born, who some years ago, had once been investigated in relation to concerns about violent extremism.

He was, she explained, a peripheral figure and was not part of the current intelligence picture. There was no prior intelligence of his intent or of the plot, she assured MPs. However, this latter reference seemed to have been the PM misspeaking because, as yet, no plot has been uncovered.

As she praised the police and emergency services, the PM suggested that the best message that could be sent to those who sought to frighten and cow us was the “millions of acts of normality” as ordinary people went about their daily lives uncowed and defiant in the face of terror.

“A response that denies our enemies their victory; that refuses to let them win. That shows we will never give in. A response driven by that same spirit that drove a husband and father to put himself between us and our attacker and to pay the ultimate price. A response that says to the men and women who propagate this hate and evil: you will not defeat us.

“Let this be the message from this House and this nation today: our values will prevail.”

Up in the gallery was Jean-Marc Ayrault, the French Foreign Minister, who having earlier spoken words of his country’s solidarity with Britain, decided to show it in person too.

Jeremy Corbyn also struck a tone of defiance but insisted people should not rush to judgement and wait until the police had established the full facts.

“We must stay united in our communities and not to allow fear or the voices of hatred to divide or cower us. It is by demonstrating our values of solidarity, community, humanity and love that we will defeat the poison and division of hatred.”

Angus Robertson, the SNP leader, speaking in a very calm and measured tone, declared how “notwithstanding our differences on political and constitutional issues, we are as one in our dedication to democracy, the rule of law and harmony between the peoples of all faiths and none”.

He personally wished the PM and Home Secretary well as they worked with the security and intelligence services to deal with the aftermath of the “appalling, indiscriminate terrorist act”.

Adding his gratitude to the police who ran towards danger, he insisted no terrorist outrage represented any faith and insisted society would recommit itself to strengthen the bonds of tolerance and understanding.

To hear hears, he quoted the remarks of Brendan Cox, the widower of Jo Cox, who said: “’In the days to come I hope we will remember the love and bravery of the victim and not just the hatred and cowardice of the attacker.’”

Later, MP after MP stood up to make it clear that terrorism, in all its different forms, would never win.

Former Conservative leader Iain Duncan Smith said Westminster had been targeted by terrorists because “we are a beacon of freedom”.

Tim Farron, the Liberal Democrat leader, said: “Those who attack us hate our freedom, our peaceful democracy, our love of country, our tolerance, our openness and our unity,” and stressed these should not be curtailed in the face of a terrorist attack.

Harriet Harman, the former deputy Labour leader, said Parliament was so proud of the bravery of Keith Palmer but also so sad at the loss for his family.

She told MPs that the horrific crime had failed as an act of terror. “It has failed because we are here and we are going to go about our business…[and] it has failed because we are not going to allow this to be used as a pretext for hatred, division and Islamophobia.”

MP after MP also rose to praise the tone and content of the PM’s speech, saying she had spoken on behalf of not only the whole House and but also the nation.

One was Ed Miliband, the former Labour leader, who said: “Can I join others in commending the Prime Minister for her statement last night and her statement today; in her tone and substance she has spoken for the whole country and I commend her for it.”

He stressed that no one should try to divide Britain on the basis of faith and nationality. “The reality is across London and across the country, we are united against these attacks; that is who we are.”

His Labour colleague Yvette Cooper, added her praise for the PM’s remarks and said the terrorist act was a “cowardly attack on our freedom,” which had failed not least because of the partnership between the police and community.

Mrs May, who also hailed the “unique bond” between the police and local people, ended on another defiant note as she made clear to MPs: “This country will not be cowed by these terrorists.”